World's Oceans Got a Lot Warmer In 2013

By Terrell Johnson

Published Feb 5 2014 05:08 PM EST

weather.com

Enlarge

{{internalImg.image_caption + " "}}

Global ocean temperatures rose dramatically last year, providing another strong sign that the oft-cited global warming "pause" or "hiatus" since 2000 has happened only at the surface – while the rest of the planet has been heating up at an increasingly rapid pace.

This chart from NOAA's National Oceanographic Data Center shows the rise in global ocean heat content in the upper 2,000 meters (the top 6,500 feet) of the oceans since the mid 1950s, with the sharpest rise occurring since about 1990:

Enlarge

{{internalImg.image_caption + " "}}

As you'll see at the left side of the chart, the ocean's heat is measured in joules, a unit of energy. Over the past 55 years, the global ocean has warmed at a rate of about 136 trillion joules per second, a pace that's been compared to the amount of energy released by two Hiroshima atomic bombs – every second.

In more recent years, that pace has quickened to about 250 trillion joules per second, or roughly four atomic bombs per second. And in 2013, that pace accelerated even more, roughly tripling to about 12 atomic bombs per second.

This is significant because, as the Intergovernmental Panel on Climate Change notes in its 2013 report, the world's oceans are absorbing more than 90 percent of the rise in heat stored by the climate system over the past few decades – far more than land, ice, or the atmosphere, which stores only about 2 percent of the excess heat.

Enlarge

{{internalImg.image_caption + " "}}

That means that global average surface temperature measurements, which have showed a slowdown in warming since about 2000, are just one indicator of how much and how quickly the planet is warming.

As the IPCC points out, there are a slew of other measurements – like the increasingly rapid melting of the world's glacial ice, Arctic sea ice and the Greenland ice sheet – that demonstrate how misleading that one indicator can be if we look at it in isolation.